1. Field of the Invention
This invention relates generally to a method and apparatus for enabling an opening and closing of a hinged door and, more particularly, to a method and apparatus for enabling an opening and closing of a ventilation door used in a poultry house or hog barn.
2. Discussion of the Related Art
In various industries such as those involving agriculture, it is often necessary to circulate relatively large amounts of air through a building to help maintain the interior of the building within a desired temperature range and to provide adequate ventilation. One such application where ventilation and control of the temperature within a building is extremely important is in connection with poultry houses. Such facilities are typically used to house chickens which are being grown for eventual slaughter or which are being used for egg production. Turkeys are also commonly kept in such poultry houses, although turkeys have been found to be somewhat less sensitive than chickens to large variations in the ambient temperature within the poultry house.
In a large scale poultry house, typically twenty thousand to twenty-five thousand chickens may be housed at a given time. If a poultry house is not properly ventilated, and the ambient temperature within it not properly controlled, the respiration of the chickens and the waste by-products within the poultry house can quickly give rise to a build up of ammonia and heat within the house which may be physiologically detrimental to the chickens. In extreme cases, such as where adequate ventilation and/or cooling is not provided on hot summer days, significant animal mortality may result. Even if mortality does not result, repeated lapses of proper ventilation and/or cooling can produce significant physiological stress on the chickens that result in inhibited growth, reduced egg production, and/or disease. Any of the above conditions may result in significant financial losses to a poultry farmer.
The problem with providing proper ventilation and cooling within a poultry house is exacerbated by the physiological differences between poultry of different ages. For example, very young chickens, hereafter referred to as "chicks", are more tolerant of higher temperatures than older chickens but also more sensitive to lower temperatures. It has been found that chicks suffer abnormal mortality below about 68.degree.-70.degree. F. However, chicks tolerate temperatures into the high 80.degree. F. range quite well. More mature chickens, however, are much more tolerant of lower temperatures but become more susceptible to mortality as the ambient temperature within a poultry house without proper ventilation and cooling, reaches into the 80.degree. F. range. Since chicks and more mature chickens must be housed in the same poultry house, this further increases the criticality of maintaining proper ventilation and a predetermined temperature range within the poultry house.
Further complicating the control of ventilation and temperature within poultry houses is the significant temperature swings experienced during many summer months and during various parts of the day. For example, during the summer months the outside temperature is typically warmest between about 2:00 p.m. and 5:00 p.m. In the early evening, such as around 5:00 p.m., any slight wind or breeze present during the day typically dies down. Accordingly, the heat build up within a poultry house without proper cooling can become critically high. Simultaneously, since little or no breeze is present, ventilation within the poultry house, can also become critically poor, leading to an unacceptably high level of ammonia buildup in the building. Within a matter of hours, however, as evening approaches, the ambient temperature may drop significantly. Thus, the need for significant cooling within the poultry house may lessen or be completely eliminated. In this instance, adequate ventilation may be accomplished without the use of power driven cooling implements such as fans. The same situation may arise with the approach of an afternoon thunderstorm. The ambient temperature may drop significantly within a matter of an hour or less while the wind speed of the ambient air may increase significantly.
The above considerations dictate that a plurality of ventilation and cooling devices be used to insure proper ventilation and relatively close control over the ambient temperature within a poultry house. Typically, this requires the use of one or more passive or active ventilation devices be used in the poultry house. Such devices typically include power driven curtains for opening large portions of the poultry house, elongated ventilation opening extending about the upper periphery of the poultry house to provide additional cross ventilation through the poultry house, and various ventilation and exhaust fans disposed within the poultry house, as well as about various walls of the poultry house for drawing air into and through the poultry house, via the large curtained openings and/or the elongated ventilation openings. Typically, each elongated ventilation opening includes a ventilation door and frame assembly that is framed into the wall of the poultry house. To control the opening and closing of the ventilation doors, a pulley and linkage system driven by a motor is coupled to each ventilation door by means of a bracket extending from each hinged door.
While the existing brackets on the ventilation doors work well in connecting the ventilation doors with the pulley and linkage system, there are, however, several disadvantages associated with the use of the currently existing brackets. For example, since the brackets extend out several inches from the ventilation doors, the brackets are prone to being bent or broken off during packaging and transport. Because of this, each bracket is packaged separately from the ventilation door to reduce the chance of damage. The un-assembled bracket, however, causes additional disadvantages. In this regard, a poultry house will generally have several dozen ventilation doors. As a result, several dozen individual brackets, as well as several hundred pop rivets or sheet metal screws used to secure the brackets must be subsequently assembled to the ventilation doors by use of tools after the ventilation doors have been installed into the poultry house. This installation process is very time consuming and thereby prone to improper assembly.
What is needed then is a method and apparatus for enabling an opening and closing of a ventilation door used in a poultry house which does not suffer from the above mentioned disadvantages. This will, in turn, eliminate the need to separately ship the door bracket, eliminate subsequent assembly of the door bracket, eliminate the need for utilizing pop rivets or sheet metal screws during the assembly, eliminate the possibility of losing separate brackets or hardware, eliminate the need for tools to put the bracket into operation, reduce the installation time and complexity, reduce the potential of damaging the bracket during packaging and shipping, and reduce the overall installation cost by reducing a significant installation step. It is, therefore, an object of the present invention to provide such a method and apparatus for enabling an opening and closing of a ventilation door used in a poultry house.